And next, tonight, we move to an ABC news investigation, with those new terror warnings about security during the winter olympics. Today, Russia arrested two brothers for a link to recent bombings. So, this is the question -- if sochi is such a hotbed for terrorism, why was it chosen as the public site anyway? Brian Ross, in search of those answers. Reporter: This year's winter olympics could have been held in the storied villages of the Austrian alps. Or the mountains of South Korea, a snowboarder's paradise. Instead, the international olympic committee chose a subtropical city in Russia, famed for its black sea summer beaches, where snow rarely falls. And located a few hundred miles from the stronghold of a ruthless terror group that has declared war on the olympics. So, now, the question is being asked, why was sochi picked in the first place? The choice of sochi is the best choice. Reporter: Russian president Vladimir Putin pushed hard to win the 2014 games for sochi. But an ABC news investigation has found, that behind the scenes, Russia was helped in getting the votes by this mysterious businessman, gafur rakhimov, who U.S. Authorities say is a key member in one of the world's biggest organized crime networks, involving the trafficking of heroin across Russia into Europe. He's absolutely a very major and very dangerous gangster. Reporter: Yet, rakhimov, seen here at a 2012 olympic event, has been thanked by the Russian olympic committee for his single-minded work in delivering the votes of certain asian countries, without which, it would have been hard for sochi to count on the victory. Rakhimov is a powerful figure in Russian media, with friends in the mafia and in the kremlin. Quote, he convinced them because of his good relations with these people. He has great influence, the spokesperson said. And he added, no bribes were necessary. The international olympic committee says its bidding process is strong and transparent. But neither it or president Putin's office would respond directly to our questions about how this accused heroin kingpin apparently has such friends and influence with both the olympics and the kremlin, Diane. Thank you so much, Brian.

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